DE412287C - Device for measuring an average value for multi-phase alternating current from the currents, voltages or powers of the individual phases - Google Patents

Description

Device for measuring an average value for multiphase alternating current from the currents, voltages or powers of the individual phases. For certain cases especially for the sale of electricity, it is important to have an unequal loaded three-phase system or one with different phase voltages to measure the currents or the voltages of the individual phases, but rather those Average value that is decisive for the active power or reactive power.

The invention consists in the fact that the movements of in the individual phases switched on measuring devices mechanically directly or indirectly transfers to as many points on a body which are so situated to one another that Another point of the body so influenced is to be found, the movement of which is proportional is the mean of all measured individual phase values and in a suitable `` '' way is used to display this mean value.

You can do this using three single-phase alternating current voltmeters in a corresponding arrangement and combination mechanically a mean voltage value determine for all three voltages or by means of three single-phase alternating current meters an average current strength or with a corresponding combination of line meters also an average output or, if counters are used instead of knives, also one mean number of ampere-hours or a mean number of kilovolt-ampere or kilowatt-hours, that is, a mean total work, determine or directly measured that in the offsetting the energy or work consumed in order to take account of the phase shift between current and voltage in each phase, especially when offsetting according to kilovolt-amperes, is particularly important.

In the drawing is an embodiment according to the invention shown as an ammeter for a three-phase system with unevenly loaded phases. Fig. I is a schematic diagram of such a device for measuring the mean Amperage, while at the same time for the purpose of better understanding the Stromrauchsanlaa is indicated with.

An essentially simultaneously triangular body i is suspended in its center of gravity: 2 on a cord G which is guided via an easily rotatable pulley or cord disc 8 to a spring 7 attached on the other side to the frame of the device. Three an equilateral triangle with the center in Figure 2, the center of gravity of the body i, forming points 3, 4, 5 of the body i engage three Einphasenstrommesser a, b, c by means of lines 12, 13, 14 at. The spring 7 can be adjusted by means of a screw for the purpose of setting the triangular body i in the correct position so that in the zero position the cores of the three measuring devices lie against the fixed abutment ii.

The roller 8 is rigidly connected to the pointer 9 in front of a scale io plays.

It can be mathematically proven that the movements of the center of gravity of the equilateral triangle 3, 4, 5, taking into account the tensile forces of the ammeters a, b, c acting like gravity on the points 3, 4, 5 are a measure of the mean value of the is three single-phase currents, which can also be read on the knives a, b, c.

Because of the phase shift in the lines and machines The electricity companies now usually do not calculate the resulting disadvantages according to kilowatt, but by kilovoltamper hours, and as a result one can use the one described above Use equipment with ammeters also to measure the mean kilovolt ampere, if one sets a practically constant tension as a basis. If you leave the pointer 9 automatically write down the mean values, so one has gained from the Current curve diagram, taking into account the time and the voltage, also the mean one The power or the average kilovolt-ampere hourly consumption of the three can vary as desired loaded phases of the system.

In a corresponding manner, voltmeters can also be used instead of ammeters are manufactured according to the invention or, if properly assembled, also real Kilovolt ampere meter or kilovolt ampere meter, in which the voltage changes, which can sometimes be quite considerable are taken into account.

In the case of two-phase or multi-phase alternating current, in a corresponding manner be proceeded, with two, three or more correspondingly on the body instead of three i arranged points of the connection of the single-phase measuring devices of the individual phases of the system.

Claims (1)

PATENT CLAIMS: i. Device for measuring a mean value at Multiphase alternating current from the currents, voltages or powers of each Phases, characterized in that measuring devices are switched on in the individual phases are whose movements are mechanically direct or indirect on as many points of a body that are so located to each other that another Point of the body so influenced is to be found, the movement of which is proportional to the Is the mean value of all measured single phase values and this mean value is more suitable Way to display. 2: Device according to claim i, for three-phase current, characterized characterized in that a resilient (by means of spring 7) suspended in its center of gravity (2) Body (i) is provided in which in three an equilateral triangle with the center in the center of gravity of this body forming points the measuring instruments of the three phases cles Attack the system and counteract the effect by moving the center of gravity the spring (7) directly or indirectly a display device (9, io) for the Mean value from the measurements of the three individual phases is actuated.